pci-skeleton.c

宋宝华的《Linux设备驱动开发详解》第一版的源代码

		if ((tmp8 & CmdRxEnb) && (tmp8 & CmdTxEnb))
			break;
		NETDRV_W8_F (ChipCmd,
			  (tmp8 & ChipCmdClear) | CmdRxEnb | CmdTxEnb);
	}

	/* G.S.: Re-enable receiver */
	/* XXX temporary hack to work around receiver hang */
	netdrv_set_rx_mode (dev);

	if (tmp_work <= 0)
		printk (KERN_WARNING PFX "tx/rx enable wait too long\n");
}


/* The data sheet doesn't describe the Rx ring at all, so I'm guessing at the
   field alignments and semantics. */
static void netdrv_rx_interrupt (struct net_device *dev,
				  struct netdrv_private *tp, void *ioaddr)
{
	unsigned char *rx_ring;
	u16 cur_rx;

	assert (dev != NULL);
	assert (tp != NULL);
	assert (ioaddr != NULL);

	rx_ring = tp->rx_ring;
	cur_rx = tp->cur_rx;

	DPRINTK ("%s: In netdrv_rx(), current %4.4x BufAddr %4.4x,"
		 " free to %4.4x, Cmd %2.2x.\n", dev->name, cur_rx,
		 NETDRV_R16 (RxBufAddr),
		 NETDRV_R16 (RxBufPtr), NETDRV_R8 (ChipCmd));

	while ((NETDRV_R8 (ChipCmd) & RxBufEmpty) == 0) {
		int ring_offset = cur_rx % RX_BUF_LEN;
		u32 rx_status;
		unsigned int rx_size;
		unsigned int pkt_size;
		struct sk_buff *skb;

		/* read size+status of next frame from DMA ring buffer */
		rx_status = le32_to_cpu (*(u32 *) (rx_ring + ring_offset));
		rx_size = rx_status >> 16;
		pkt_size = rx_size - 4;

		DPRINTK ("%s:  netdrv_rx() status %4.4x, size %4.4x,"
			 " cur %4.4x.\n", dev->name, rx_status,
			 rx_size, cur_rx);
#if NETDRV_DEBUG > 2
		{
			int i;
			DPRINTK ("%s: Frame contents ", dev->name);
			for (i = 0; i < 70; i++)
				printk (" %2.2x",
					rx_ring[ring_offset + i]);
			printk (".\n");
		}
#endif

		/* If Rx err or invalid rx_size/rx_status received
		 * (which happens if we get lost in the ring),
		 * Rx process gets reset, so we abort any further
		 * Rx processing.
		 */
		if ((rx_size > (MAX_ETH_FRAME_SIZE+4)) ||
		    (!(rx_status & RxStatusOK))) {
			netdrv_rx_err (rx_status, dev, tp, ioaddr);
			return;
		}

		/* Malloc up new buffer, compatible with net-2e. */
		/* Omit the four octet CRC from the length. */

		/* TODO: consider allocating skb's outside of
		 * interrupt context, both to speed interrupt processing,
		 * and also to reduce the chances of having to
		 * drop packets here under memory pressure.
		 */

		skb = dev_alloc_skb (pkt_size + 2);
		if (skb) {
			skb->dev = dev;
			skb_reserve (skb, 2);	/* 16 byte align the IP fields. */

			eth_copy_and_sum (skb, &rx_ring[ring_offset + 4], pkt_size, 0);
			skb_put (skb, pkt_size);

			skb->protocol = eth_type_trans (skb, dev);
			netif_rx (skb);
			dev->last_rx = jiffies;
			tp->stats.rx_bytes += pkt_size;
			tp->stats.rx_packets++;
		} else {
			printk (KERN_WARNING
				"%s: Memory squeeze, dropping packet.\n",
				dev->name);
			tp->stats.rx_dropped++;
		}

		cur_rx = (cur_rx + rx_size + 4 + 3) & ~3;
		NETDRV_W16_F (RxBufPtr, cur_rx - 16);
	}

	DPRINTK ("%s: Done netdrv_rx(), current %4.4x BufAddr %4.4x,"
		 " free to %4.4x, Cmd %2.2x.\n", dev->name, cur_rx,
		 NETDRV_R16 (RxBufAddr),
		 NETDRV_R16 (RxBufPtr), NETDRV_R8 (ChipCmd));

	tp->cur_rx = cur_rx;
}


static void netdrv_weird_interrupt (struct net_device *dev,
				     struct netdrv_private *tp,
				     void *ioaddr,
				     int status, int link_changed)
{
	printk (KERN_DEBUG "%s: Abnormal interrupt, status %8.8x.\n",
		dev->name, status);

	assert (dev != NULL);
	assert (tp != NULL);
	assert (ioaddr != NULL);

	/* Update the error count. */
	tp->stats.rx_missed_errors += NETDRV_R32 (RxMissed);
	NETDRV_W32 (RxMissed, 0);

	if ((status & RxUnderrun) && link_changed &&
	    (tp->drv_flags & HAS_LNK_CHNG)) {
		/* Really link-change on new chips. */
		int lpar = NETDRV_R16 (NWayLPAR);
		int duplex = (lpar & 0x0100) || (lpar & 0x01C0) == 0x0040
				|| tp->duplex_lock;
		if (tp->full_duplex != duplex) {
			tp->full_duplex = duplex;
			NETDRV_W8 (Cfg9346, Cfg9346_Unlock);
			NETDRV_W8 (Config1, tp->full_duplex ? 0x60 : 0x20);
			NETDRV_W8 (Cfg9346, Cfg9346_Lock);
		}
		status &= ~RxUnderrun;
	}

	/* XXX along with netdrv_rx_err, are we double-counting errors? */
	if (status &
	    (RxUnderrun | RxOverflow | RxErr | RxFIFOOver))
		tp->stats.rx_errors++;

	if (status & (PCSTimeout))
		tp->stats.rx_length_errors++;
	if (status & (RxUnderrun | RxFIFOOver))
		tp->stats.rx_fifo_errors++;
	if (status & RxOverflow) {
		tp->stats.rx_over_errors++;
		tp->cur_rx = NETDRV_R16 (RxBufAddr) % RX_BUF_LEN;
		NETDRV_W16_F (RxBufPtr, tp->cur_rx - 16);
	}
	if (status & PCIErr) {
		u16 pci_cmd_status;
		pci_read_config_word (tp->pci_dev, PCI_STATUS, &pci_cmd_status);

		printk (KERN_ERR "%s: PCI Bus error %4.4x.\n",
			dev->name, pci_cmd_status);
	}
}


/* The interrupt handler does all of the Rx thread work and cleans up
   after the Tx thread. */
static irqreturn_t netdrv_interrupt (int irq, void *dev_instance,
			       struct pt_regs *regs)
{
	struct net_device *dev = (struct net_device *) dev_instance;
	struct netdrv_private *tp = dev->priv;
	int boguscnt = max_interrupt_work;
	void *ioaddr = tp->mmio_addr;
	int status = 0, link_changed = 0; /* avoid bogus "uninit" warning */
	int handled = 0;

	spin_lock (&tp->lock);

	do {
		status = NETDRV_R16 (IntrStatus);

		/* h/w no longer present (hotplug?) or major error, bail */
		if (status == 0xFFFF)
			break;

		handled = 1;
		/* Acknowledge all of the current interrupt sources ASAP */
		NETDRV_W16_F (IntrStatus, status);

		DPRINTK ("%s: interrupt  status=%#4.4x new intstat=%#4.4x.\n",
				dev->name, status,
				NETDRV_R16 (IntrStatus));

		if ((status &
		     (PCIErr | PCSTimeout | RxUnderrun | RxOverflow |
		      RxFIFOOver | TxErr | TxOK | RxErr | RxOK)) == 0)
			break;

		/* Check uncommon events with one test. */
		if (status & (PCIErr | PCSTimeout | RxUnderrun | RxOverflow |
		  	      RxFIFOOver | TxErr | RxErr))
			netdrv_weird_interrupt (dev, tp, ioaddr,
						 status, link_changed);

		if (status & (RxOK | RxUnderrun | RxOverflow | RxFIFOOver))	/* Rx interrupt */
			netdrv_rx_interrupt (dev, tp, ioaddr);

		if (status & (TxOK | TxErr))
			netdrv_tx_interrupt (dev, tp, ioaddr);

		boguscnt--;
	} while (boguscnt > 0);

	if (boguscnt <= 0) {
		printk (KERN_WARNING
			"%s: Too much work at interrupt, "
			"IntrStatus=0x%4.4x.\n", dev->name,
			status);

		/* Clear all interrupt sources. */
		NETDRV_W16 (IntrStatus, 0xffff);
	}

	spin_unlock (&tp->lock);

	DPRINTK ("%s: exiting interrupt, intr_status=%#4.4x.\n",
		 dev->name, NETDRV_R16 (IntrStatus));
	return IRQ_RETVAL(handled);
}


static int netdrv_close (struct net_device *dev)
{
	struct netdrv_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	unsigned long flags;

	DPRINTK ("ENTER\n");

	netif_stop_queue (dev);

	DPRINTK ("%s: Shutting down ethercard, status was 0x%4.4x.\n",
			dev->name, NETDRV_R16 (IntrStatus));

	del_timer_sync (&tp->timer);

	spin_lock_irqsave (&tp->lock, flags);

	/* Stop the chip's Tx and Rx DMA processes. */
	NETDRV_W8 (ChipCmd, (NETDRV_R8 (ChipCmd) & ChipCmdClear));

	/* Disable interrupts by clearing the interrupt mask. */
	NETDRV_W16 (IntrMask, 0x0000);

	/* Update the error counts. */
	tp->stats.rx_missed_errors += NETDRV_R32 (RxMissed);
	NETDRV_W32 (RxMissed, 0);

	spin_unlock_irqrestore (&tp->lock, flags);

	synchronize_irq ();
	free_irq (dev->irq, dev);

	netdrv_tx_clear (tp);

	pci_free_consistent(tp->pci_dev, RX_BUF_TOT_LEN,
			    tp->rx_ring, tp->rx_ring_dma);
	pci_free_consistent(tp->pci_dev, TX_BUF_TOT_LEN,
			    tp->tx_bufs, tp->tx_bufs_dma);
	tp->rx_ring = NULL;
	tp->tx_bufs = NULL;

	/* Green! Put the chip in low-power mode. */
	NETDRV_W8 (Cfg9346, Cfg9346_Unlock);
	NETDRV_W8 (Config1, 0x03);
	NETDRV_W8 (Cfg9346, Cfg9346_Lock);

	DPRINTK ("EXIT\n");
	return 0;
}


static int netdrv_ioctl (struct net_device *dev, struct ifreq *rq, int cmd)
{
	struct netdrv_private *tp = dev->priv;
	struct mii_ioctl_data *data = if_mii(rq);
	unsigned long flags;
	int rc = 0;

	DPRINTK ("ENTER\n");

	switch (cmd) {
	case SIOCGMIIPHY:		/* Get address of MII PHY in use. */
		data->phy_id = tp->phys[0] & 0x3f;
		/* Fall Through */

	case SIOCGMIIREG:		/* Read MII PHY register. */
		spin_lock_irqsave (&tp->lock, flags);
		data->val_out = mdio_read (dev, data->phy_id & 0x1f, data->reg_num & 0x1f);
		spin_unlock_irqrestore (&tp->lock, flags);
		break;

	case SIOCSMIIREG:		/* Write MII PHY register. */
		if (!capable (CAP_NET_ADMIN)) {
			rc = -EPERM;
			break;
		}

		spin_lock_irqsave (&tp->lock, flags);
		mdio_write (dev, data->phy_id & 0x1f, data->reg_num & 0x1f, data->val_in);
		spin_unlock_irqrestore (&tp->lock, flags);
		break;

	default:
		rc = -EOPNOTSUPP;
		break;
	}

	DPRINTK ("EXIT, returning %d\n", rc);
	return rc;
}


static struct net_device_stats *netdrv_get_stats (struct net_device *dev)
{
	struct netdrv_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;

	DPRINTK ("ENTER\n");

	assert (tp != NULL);

	if (netif_running(dev)) {
		unsigned long flags;

		spin_lock_irqsave (&tp->lock, flags);

		tp->stats.rx_missed_errors += NETDRV_R32 (RxMissed);
		NETDRV_W32 (RxMissed, 0);

		spin_unlock_irqrestore (&tp->lock, flags);
	}

	DPRINTK ("EXIT\n");
	return &tp->stats;
}

/* Set or clear the multicast filter for this adaptor.
   This routine is not state sensitive and need not be SMP locked. */

static void netdrv_set_rx_mode (struct net_device *dev)
{
	struct netdrv_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	u32 mc_filter[2];	/* Multicast hash filter */
	int i, rx_mode;
	u32 tmp;

	DPRINTK ("ENTER\n");

	DPRINTK ("%s:   netdrv_set_rx_mode(%4.4x) done -- Rx config %8.8x.\n",
			dev->name, dev->flags, NETDRV_R32 (RxConfig));

	/* Note: do not reorder, GCC is clever about common statements. */
	if (dev->flags & IFF_PROMISC) {
		/* Unconditionally log net taps. */
		printk (KERN_NOTICE "%s: Promiscuous mode enabled.\n",
			dev->name);
		rx_mode =
		    AcceptBroadcast | AcceptMulticast | AcceptMyPhys |
		    AcceptAllPhys;
		mc_filter[1] = mc_filter[0] = 0xffffffff;
	} else if ((dev->mc_count > multicast_filter_limit)
		   || (dev->flags & IFF_ALLMULTI)) {
		/* Too many to filter perfectly -- accept all multicasts. */
		rx_mode = AcceptBroadcast | AcceptMulticast | AcceptMyPhys;
		mc_filter[1] = mc_filter[0] = 0xffffffff;
	} else {
		struct dev_mc_list *mclist;
		rx_mode = AcceptBroadcast | AcceptMulticast | AcceptMyPhys;
		mc_filter[1] = mc_filter[0] = 0;
		for (i = 0, mclist = dev->mc_list; mclist && i < dev->mc_count;
		     i++, mclist = mclist->next) {
			int bit_nr = ether_crc(ETH_ALEN, mclist->dmi_addr) >> 26;

			mc_filter[bit_nr >> 5] |= 1 << (bit_nr & 31);
		}
	}

	/* if called from irq handler, lock already acquired */
	if (!in_irq ())
		spin_lock_irq (&tp->lock);

	/* We can safely update without stopping the chip. */
	tmp = netdrv_rx_config | rx_mode |
		(NETDRV_R32 (RxConfig) & rtl_chip_info[tp->chipset].RxConfigMask);
	NETDRV_W32_F (RxConfig, tmp);
	NETDRV_W32_F (MAR0 + 0, mc_filter[0]);
	NETDRV_W32_F (MAR0 + 4, mc_filter[1]);

	if (!in_irq ())
		spin_unlock_irq (&tp->lock);

	DPRINTK ("EXIT\n");
}


#ifdef CONFIG_PM

static int netdrv_suspend (struct pci_dev *pdev, pm_message_t state)
{
	struct net_device *dev = pci_get_drvdata (pdev);
	struct netdrv_private *tp = dev->priv;
	void *ioaddr = tp->mmio_addr;
	unsigned long flags;

	if (!netif_running(dev))
		return 0;
	netif_device_detach (dev);

	spin_lock_irqsave (&tp->lock, flags);

	/* Disable interrupts, stop Tx and Rx. */
	NETDRV_W16 (IntrMask, 0x0000);
	NETDRV_W8 (ChipCmd, (NETDRV_R8 (ChipCmd) & ChipCmdClear));

	/* Update the error counts. */
	tp->stats.rx_missed_errors += NETDRV_R32 (RxMissed);
	NETDRV_W32 (RxMissed, 0);

	spin_unlock_irqrestore (&tp->lock, flags);

	pci_save_state (pdev);
	pci_set_power_state (pdev, PCI_D3hot);

	return 0;
}


static int netdrv_resume (struct pci_dev *pdev)
{
	struct net_device *dev = pci_get_drvdata (pdev);
	struct netdrv_private *tp = dev->priv;

	if (!netif_running(dev))
		return 0;
	pci_set_power_state (pdev, PCI_D0);
	pci_restore_state (pdev);
	netif_device_attach (dev);
	netdrv_hw_start (dev);

	return 0;
}

#endif /* CONFIG_PM */


static struct pci_driver netdrv_pci_driver = {
	.name		= MODNAME,
	.id_table	= netdrv_pci_tbl,
	.probe		= netdrv_init_one,
	.remove		= __devexit_p(netdrv_remove_one),
#ifdef CONFIG_PM
	.suspend	= netdrv_suspend,
	.resume		= netdrv_resume,
#endif /* CONFIG_PM */
};


static int __init netdrv_init_module (void)
{
/* when a module, this is printed whether or not devices are found in probe */
#ifdef MODULE
	printk(version);
#endif
	return pci_module_init (&netdrv_pci_driver);
}


static void __exit netdrv_cleanup_module (void)
{
	pci_unregister_driver (&netdrv_pci_driver);
}


module_init(netdrv_init_module);
module_exit(netdrv_cleanup_module);